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The interaction of microquasar jets with their environment can produce non-thermal radiation as is the case for extragalactic outflows impacting on their surroundings. We have developed an analytical model based on those successfully…

Astrophysics · Physics 2009-11-13 P. Bordas , V. Bosch-Ramon , J. M. Paredes , M. Perucho

In active galactic nuclei, the relationship between UV and X-ray luminosity is well studied (often characterised by $\alpha_\text{ox}$) but often with heterogeneous samples. We have parametrized the intrinsic distribution of X-ray…

Astrophysics of Galaxies · Physics 2023-11-29 Amy L. Rankine , James Aird , Angel Ruiz , Antonis Georgakakis

We present an extended optical monitoring of the quadruply-imaged gravitationally lensed quasar QSO 2237+0305, the Einstein Cross, including observations from different observatories in both hemispheres and using a new photometric…

The non-linear relation between the UV and X-ray luminosity in quasars has been studied for decades. However, as we lack a comprehensive model able to explain it, its investigation still relies on observational efforts. This work focuses on…

High Energy Astrophysical Phenomena · Physics 2025-11-19 Andrea Sacchi , Guido Risaliti , Matilde Signorini , Emanuele Nardini , Elisabeta Lusso , Bartolomeo Trefoloni

We present the results of timing and spectral analysis of the blazar H 2356-309 using XMM-Newton observations. This blazar is observed during 13 June 2005-24 December 2013 in total nine observations. Five of the observations show moderate…

High Energy Astrophysical Phenomena · Physics 2020-09-07 Kiran A. Wani , Haritma Gaur

We present the analysis of Suzaku and XMM-Newton observations of the broad-line radio galaxy (BLRG) 3C 111. Its high energy emission shows variability, a harder continuum with respect to the radio quiet AGN population, and weak reflection…

High Energy Astrophysical Phenomena · Physics 2015-05-30 L. Ballo , V. Braito , J. N. Reeves , R. M. Sambruna , F. Tombesi

We investigate MeV-GeV $\gamma$-ray outbursts in 3C 273 in the frame of a time-dependent one-zone synchrotron self-Compton (SSC) model. In this model, electrons are accelerated to extra-relativistic energy through the stochastic particle…

High Energy Astrophysical Phenomena · Physics 2016-08-02 Y. G. Zheng , L. Zhang , B. R. Huang , S. J. Kang

During its strong outburst of 2015 June/July, the X-ray transient V404 Cygni (= GS2023+338) was observed up to a level of 50 Crab in the hard X-ray domain. We focus here on a particularly intense episode preceeding a definitive decline of…

High Energy Astrophysical Phenomena · Physics 2017-01-18 Elisabeth Jourdain , Jean-Pierre Roques , James Rodi

We present Gemini Multiobject Spectrograph integral field spectroscopy of the extended emission-line region associated with quasar 3C 249.1. The kinematics of the ionized gas measured from the [O III] $\lambda$5007 line is rather complex…

Astrophysics · Physics 2011-02-11 Hai Fu , Alan Stockton

This paper presents the analysis of Chandra X-ray snapshot observations of a subsample of the extragalactic sources listed in the revised Third Cambridge radio catalog (3CR), previously lacking X-ray observations and thus observed during…

We try to explain the unusually high far-infrared emission seen by IRAS in the double-lobed radio-loud quasars 3C47, 3C207 and 3C334. High resolution cm--mm observations were carried out to determine their radio core spectra, which are…

Astrophysics · Physics 2007-05-23 Ilse M. van Bemmel , Peter D. Barthel , Min S. Yun

We report a time-resolved analysis of the accreting X-ray pulsar Cen X-3 using observations carried out by NuSTAR, which cover approximately two binary orbits in different intensity states. The pulse profile is relatively stable over the…

High Energy Astrophysical Phenomena · Physics 2024-10-30 Qi Liu , Wei Wang , Andrea Santangelo , Lingda Kong , Long Ji , Lorenzo Ducci

We have studied finite $N$-body $D$-dimensional nonextensive ideal gases and harmonic oscillators, by using the maximum-entropy methods with the $q$- and normal averages ($q$: the entropic index). The validity range, specific heat and…

Statistical Mechanics · Physics 2015-05-18 Hideo Hasegawa

We investigate the type III radio bursts and X-ray signatures of accelerated electrons in a well observed solar flare in order to find the spatial properties of the acceleration region. Combining simultaneous RHESSI hard X-ray flare data…

Solar and Stellar Astrophysics · Physics 2015-05-27 H. A. S. Reid , N. Vilmer , E. P. Kontar

We use a sample of 332 Hubble Space Telescope spectra of 184 QSOs with z > 0.33 to study the typical ultraviolet spectral properties of QSOs, with emphasis on the ionizing continuum. Our sample is nearly twice as large as that of Zheng et…

Astrophysics · Physics 2016-08-30 R. C. Telfer , W. Zheng , G. A. Kriss , A. F. Davidsen

We present light curves for 149 sources monitored with the Green Bank Interferometer. The light curves are at two radio frequencies (approximately 2.5 and 8.2 GHz) and range from 3 to 15 yrs in length, covering the interval 1979--1996, and…

We introduce an investigation about M dimers through half-filled two-site Hubbard model, that is, with two electrons. We utilize the third version of nonextensive statistical mechanics as tool for cal-culating thermodynamical and magnetic…

Statistical Mechanics · Physics 2010-02-16 F. A. R. Navarro , J. F. V. Flores

We present multiwavelength observations of Cygnus X-3 during an extended outburst in 1994 February - March. Intensive radio monitoring at 13.3, 3.6 & 2.0 cm is complemented by observations at (sub)millimetre and infrared wavelengths, which…

Astrophysics · Physics 2015-06-24 R. P. Fender , S. J. Bell Burnell , E. B. Waltman , G. G. Pooley , F. D. Ghigo , R. S. Foster

We study the evolution of the spectral index and the normalization (flux) of the non-thermal component of the electron spectra observed by RHESSI during 24 solar hard X-ray flares. The quantitative evolution is confronted with the…

Astrophysics · Physics 2007-05-23 Paolo C. Grigis , Arnold O. Benz

We use Bayesian methods to analyze the distribution of gamma ray burst intensities reported in the Third BATSE Catalog (3B catalog) of gamma ray bursts, presuming the distribution of burst sources (``bursters'') is isotropic. We study both…

Astrophysics · Physics 2009-10-30 Thomas J. Loredo , Ira M. Wasserman